Studies On Morphological Anatomy Of Vegetative Organs And Establishment Of Regeneration Systems In Hybrid Broussonetia Papyrifera (L.) Vent

Using leaves and apical as explant,this paper studied the antiseptic disinfection,callus induction and differentiation,the optimal plant growth regulator combination and concentration in shoot proliferation and rooting,initially established high-quality variety paper mulberry regeneration system. Through paraffin section technology,callus of various status,adventitious bud formation were observed. Meanwhile,compared with morphological anatomy of stem and leaf,we obtained superior characters of hybrid paper mulberry.The main contents and results were listed as follows:1.Sampling leaf explant from cutting seedlings in greenhouse;the original explants were surface-sterilized by agitating in a solution of 0.1%HgCl₂ for 3 min,then agitated in 0.5%NaClO for 5min—two times sterilization,we could establish successfully asepsis training department.2.The young leaves and shoots of tube seedling were induced into adventitious buds;The optimal medium for leaves of callus induction and formation was MS+6-BA2.0+NAA 0.1mg/L,the best leaves for adventitious bud regeneration are the first three top leaves of a shoot which cultured for 20d;The optimal medium for shoots of callus induction and formation was MS+6-BA0.5+NAA 0.1mg/L.3.Adventitious buds subculture and proliferation,effect of cytokinin 6-BA was better than KT,the medium containing MS+6-BA1.5 or 2.0+NAA0.1mg/L was suitable for shoot proliferation,propagation coefficient reached to 4.82 and 5.56 respectively;pH was 5.60-6.80,all shoots grew normally;adding sugar 30g/L was best for growth..4.The elongation of shoots was greatly promoted by GA₃0.1-0.5mg/L in medium,as well as increased shoots number;the optimum hormone proportioning was BA2.0mg/L+NAA0.1mg/L+GA₃0.5 mg/L,propagation coefficient was up to 8.22,the shoot length was 2.94cm;adding active carbon inhibited shoot growth seriously;adding low concentration 6-BA to medium in subculture limited multiplication,while shoot elongation obviously.5.Rooting was comparatively difficult,the quality of the root system was better on MS with NAA1.0mg/L,rooting rate was 86.7%,but the roots mostly were induced from callus and not suitable to transplant.6.The paraffin slice is used to study the callus of various status and adventitious bud formation,we had observed the callus formation site on leaves,callus structure that have morphogenetic capacity,the origination modes of shoots and so forth.7.Dealing with two staining techniques,we also observed the differences of leaf morphological structure and inclusion contents between hybrid and wild paper mulberry;meanwhile through wood anatomical and resolution method,we compared to the difference of two kinds of stem segregation.